It is speculated that she is Martine Janata of the Brown Ajah, who was burned out more than twenty-five years ago while studying a ter'angreal. Setalle's current age is consistent with her having been burned out and then aging at a normal rate for twenty-five years.

She is married to Jasfer Anan. She has several children, and would have died in childbirth had it not been for the Kin.

She later accompanies Mat and his party when he flees Ebou Dar. They join up with Valan Luca's Traveling Circus where she is confined to watching over Tuon Athaem Kore Paendrag.
She accompanies Mat and Tuon on their walks together.

She interrupts Mat when he is spanking Joline and points out that he must be wearing a ter'angreal that disrupts weaves from the One Power. She says that Cadsuane Melaidhrin also has one, which surprises the Aes Sedai there, who question why she would even know Cadsuane. During this time, she reveals to Mat that she was previously Aes Sedai and left the Tower after being burned out. In return for his silence she gives some insight into Tuon's character, knowing Mat is falling for Tuon.

After a skirmish with Darkfriends in Maderin, Mat and the rest of his group decide to leave Luca's show. While riding through Altara they meet up with the Band of the Red Hand and begin to travel with them.

Furyk Karede comes to the Band's camp to take Tuon back to Ebou Dar. Tuon gives a farewell to Setalle, who she was becoming quite fond of, especially enjoying their discussions.

Setalle decides to stay with Mat's camp and take care of Olver when the Aes Sedai leave for the White Tower. She later reports to Mat about receiving a letter from Joline stating that she has made it safely to the White Tower.

She is in Tar Valon with Faile when a bubble of evil takes the group to the Blight. After Berisha's death, Faile asks her if she could make a gateway and Setalle explains that she had been burned out in an accident over twenty-five years ago. Setalle is the one to suggest going toward Shayol Ghul and Faile thinks she might be a Darkfriend.

"All three Dreamwalkers had this dream, which makes it especially significant. Rain... coming from a bowl. There are snares and pitfalls around the bowl. If the right hands pick it up, they will find a treasure perhaps as great as the bowl. In the wrong hands the world is doomed. The key to finding the bowl is to find the one who is no longer."
—Bair

It seems likely that "the one who is no longer" is indeed Setalle. It is she who takes Elayne and Nynaeve to the Kin, which eventually leads them to the Bowl of Winds. As the books progress and it seems more apparent that she was Aes Sedai (up to her ultimate confession to Mat) it might be deduced that the phrase "who is no longer" refers to her being burned out of the Source.